Ledification of many light sources and systems is nearly done. Almost all conventional products are replaced by LED versions. The first generation LED based lighting was based on so called high power LEDs. This is in comparison to LEDs used for signaling, for example on/off indicators. A high-power LED is a LED with over 1 watt energy consumption. More recently, the use of low- or mid-power LEDs seems even more attractive as, although these light sources produce less light, the lumen per dollar ratio is better than for high-power LEDs. For general lighting purposes a certain amount of lumen is needed and thus quite a few low- or mid-power LEDs. This involves a relatively large mounting surface as well and grid shaped lighting devices are seen suitable to fulfill this need, for example a grid shaped lighting device as is known from EP0645748. The known grid shaped lighting device is generally used as a cheap solution for illumination of large areas. In the known lighting device the grid is formed as a type of chicken wire construction of an electrical current conductive lead wire and a neutral wire. The lead wire and the neutral wire are attached to each other only at nodes and together form the perimeter of more or less square shaped openings, i.e. one half side of an opening is formed by the lead wire, while the opposite half side of the opening is formed by the neutral wire. In general the LEDs can only conveniently be, and are, only mounted at the nodes, thus attaining a mutual attachment of the lead wire to the neutral wire at the nodes via the LEDs. This, however, involves the risk of undesired spottiness and/or inhomogeneous illumination. To counteract said spottiness and/or inhomogeneous illumination in the known lighting device, a diffuser is mounted in front of the grid. This, however, involves the disadvantages that the overall efficiency of the known grid shaped lighting device is relatively low and its obtrusive appearance/presence in the off-state when it has little or no aesthetical value, basically a white box on the wall. Furthermore, in the known lighting device the lead wire and the neutral wire each are formed as one continuous wire to which the LEDs are connected in parallel and all the LEDs can only be switched on/off or dimmed simultaneously by a single power control. This, however, involves the disadvantage that the suitable use of the known lighting device is limited to only a relatively small number of applications.